-LRB- CNN -RRB- -- North Korea for the first time publicly specified the `` hostile acts '' that landed Kenneth Bae a 15-year sentence at a labor camp .

The Korean-American tour operator set up anti-North Korean bases in China and distributed anti-regime literature , a spokesman for the North Korean Supreme Court told the state-run KCNA news agency .

`` He committed such hostile acts as egging citizens of the DPRK overseas and foreigners on to perpetrate hostile acts to bring down its government while conducting a malignant smear campaign against it , '' the court said , using the acronym of the country 's official name , the Democratic People 's Republic of Korea .

Bae , who the North Koreans refer to as Pae Jun Ho , was arrested November 3 after arriving as a tourist in Rason city , a port in the northeastern corner of North Korea .

He was later sentenced , but authorities until now had not elaborated on what he was accused of .

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Bae was `` caught red-handed '' when he entered Rason City with anti-North Korea literature , the court said .

He was accused of preaching at churches and lecturing to groups about the need to escalate confrontation , the court said .

The statement said that the court did not allow Bae to have an attorney after he refused to give a plea , as North Korean law instructs .

Bae confessed to his crimes , the court said , according to KCNA , and `` they were clearly proved in an objective manner by evidence and testimonies . ''

In previous instances , North Korea has released Americans in its custody after a visit by some U.S. dignitary -- in recent cases , former Presidents Jimmy Carter and Bill Clinton .

But Bae 's case could get caught up in the recent tensions between North Korea and the United States .

The news comes on the heels of weeks of superheated rhetoric from North Korea , which conducted its third nuclear test in February and launched a satellite into orbit atop a long-range rocket in December . Washington responded by deploying additional missile interceptors on the West Coast , dispatching a missile defense system to the Pacific territory of Guam and bolstering annual U.S.-South Korean military exercises with overflights by nuclear-capable B-2 and B-52 bombers .

But the intensity of the North 's rhetoric appears to have subsided recently , and the U.S.-South Korean drills finished this week , removing another source of friction .

CNN 's Dana Ford , Jethro Mullen and K.J. Kwon contributed to this report .

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Korean-American Kenneth Bae was sentenced to 15 years at a labor camp

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But North Korea had not detailed the accusations against him

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A North Korean Supreme Court spokesman detailed the case to state-run media

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Bae was accused of plotting against the North Korean government